Electric switch



March 24, 1925. 1,530,664

- c. GRUNWALD ELECTRIC SWITCE Filed Dec. 24, 1921 2 Sheets-Sheet 1 March 24, 1925. 1,530,664

. A. C. GRUNWALD.

ELECTRIC SWITCH Filed Dec. 2 1921 2 Shaw-Sheet 2 Patented Mar. 24, 1925.

UNITED STATES PATIENT OFFICE.

ALBERT O. GRUNWALD, OF RIVER FOREST, ILLINOIS, ASSIGNOR 'IO PRECISION v WORKERS, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS ELECTRIC SWITCH.

Application filed December 24 Serial: N 524,699.

To all whom 2'2 may concern:

Be it known that I, ALBERT C. GRUN- wALn, a citizen ofthe United States, and.

resident of River Forest, in the countyof Cook and State of Illinois, have invented a certain new and useful Improvement in Electric Switches,- of which the following fication.

My invention relates to an electric switch for stop signal systems for the display of an indicating light at the rear of automobilcs and other vehicles.

nected with a switchcand source of current in the conventional way;

Figure 2 is an; elevation of the circuit changing switch mechanism,showing itsiap plication to a. brake rodg;

Figure 3 is a section through the switch ing mechanism on the line 7-7 of Figure-2fii Figure 4 1s an. illustration of the (,llKflllll};

changing parts of the switch mechanism of Figure 7 with. covers removed. The switchingmember illustrated generally at 42 in Figure 1, and in. detail in Figs.

2, 3 and 4, comprises a mounting'plate 43 having a central portion 44 slightly raised above the plane ofthesurface upon which the mounting plate is attached. A pair of end plates 45 and 46 support a cylinder 47 of insulating material, and also support a shaft'48, which by its rotation, performs the switching function. If desired, each of the plates 45 and 46 may be provided with inwardly turned ears X which overlie the adjacent ends of cylinder 47. Moreover a bar Y preferably connects plates 45 and 46 as shown. These end plates and the cylinder form a housing which, in operation, is preferably filled with an insulating lubricant'which also prevents moisture from entering the cylinder. Surrounding the shaft 48 and in pressed-on engagement therewith is a cylindrical member 49- of insulating material encased within a metallic cylinder 50, the latter having a small section removed at the position 51. This cylinder is preferably attached tothe insulating member 49 by" means of a pressing operation, which, through conical dies, contracts the ends of the meta-l cylinder as at 52.

An operating'handle 54 is attached to one end of the shaft 48, the said handle having a portion thereof, as at 55, formed into a section of a cylinder serving as a: guide and support for the spring 56, which, by attachment to the arm 54 at 57, and to the end plate- 46 at 58,tends to rotate the arm and 60 and 61 are mounted; these membersibeing V constructed of spring meta-l each formed with a beadGQextending longitudinally of:

the cylinder and engaging slots 63 therein. The-portions of thezspring members 60' and 61 which lie adjacent the-inner surface of the cylinder have' perforations inrthem through which the stem portions of binding posts 65'extend, the'head's- 66 on the inner ends of the. stems being provided with project'ionsregistering with: the inner concave portionsofthe beads 65, a11d being drawn firmly into position: by knurled nuts (57 which thread upon the externally projecting portionsof the stems The contacting member GO bears continually against the surface oi? the metallic cylinder 50, while the contacting member 61 normally registers with the position 51 at which the cylinder 50 is cut away, so that until the cylinder is turned from its normal position, the circuit is not completed between the contacting members 60 and 61, but when the cylinder is turned a predeterminedamount from its normal position, both of the contacting members 60 and 61 register with the cylinder and thus the circuit is completed between the binding posts 65. Y 7

The end plate46 is'provided with an upturned lug 70 which forms a normal abutment for the handle 54 to hold the shaft 48 and cylinder 50 in the open circuit position. The free end of-the handle 54 may beattached to any form of operating mechanism, and for that purpose is provided with an opening 71 into which a link 72 may be attached, the other end of the link being at- -tached to any suitable form of operating mechanism which, as shown in Figspl and 2, is a brake rod 73.

The usual storage battery of the automobile is connected in series with the switch 42 and the lamp filament Sal so that upon Jthe closure of the switch contacts, the lamp is caused to glow and display the stop signal. Under the arrangement illustrated in Fig. 1, the stop signal is displayed every time the brake pedal is depressed.

Although I have shown and described my inventionwith respect to certain details of construction, it is to be understood that these details may be modified within the skill of a mechanic without departing from the spirit orscope of my invention.

What I claim is: v

1. In a switch for a stop signal mechanism, a metal base plate adapted to be atv tached to a flat surface, shaft bearing plates carried by said base plate, said bearing plates being parallel to each other and spaced apart,1a hollow cylinder of insulating material clamped between said shaft bearing plates and with the latter constituting a closed housing, brushes carried by the inner surface of said hollow cylinder, a shaft extending through said hollow cylinder and journaled in said bearing, plates, a cylinder of insulating material carried bysaid shaft and disposed in' said hollow cylinder, a conducting sleeve disposed around and fixed to said shaft carried cylinder, said conducting sleeve having a portion thereof cut away to providearecess, and spring means associated with said shaft and normally holding said sleeve in a position such that one of said brushes extends throughsaid recess and bears against said shaft carried insulating cylinder, the other brush at all times bearing against said COIltlIlCtlllg sleeve.

2. in a switch for a stop signal mechanism, a substantially oil-tight housing comprising a hollow cylinder of insulating material and plates which are clamped against theends of said hollow cylinder, a cylinder of insulating material mounted for rotary movement within, said first-mentioned cylinder, a conducting sleeve carried by said rotary cylinder and having a recess therein, a

"shaft whercon said rotary cylinder is mounted, said shaft being journaled in said plates, a pair of brushes carried on the inner surface of said first-mentioned cylinder, one of said brushes being continuously in contact with said conducting sleeve, spring means normally holding said rotary cylinder in such position that the other brush extends through the conducting sleeve recess, and bears against the insulating material of the cylinder by which said sleeve is carried, and means :for moving the rotary cylinder to cause said last-mentioned brushto contact with the conducting sleeve.

3. In a switch forming part of a stop signal mechanism, an oil-tight housing, a nonconducting lubricant within said housing, a cylindrical member of non-conducting material mounted for movement within said housing, said non-conducting cylindrical member lying within and carrying a sleeve ofconducting material having a portion thereof cut away to-expose a portion of the cylindrical surface of the said non-conducting cylindrical member, a pair of brushes carried by sai'dfhousing and adapted to cooperate with said conducting sleeve, one of said brushes being at all times in contact with said sleeve, spring means normally holding saidcylindrical member and said sleeve in a position wherein the other brush engages the aforesaid eXposedsurf-ace of the cylindrical member and lies out of electrical engagement with said sleeve, and means for moving said cylindrical member and said sleeve against the action of said spring to eii'ect electrical connection between the sleeve and said last mentioned brush.

In witnesswhereof, I hereunto subscribe my name this 12th day of December, 1921.

' I ALBERT (3. (,lRU NW ALD. Vitnesses:

EDNA V. GUs'rArsoN, .EMILE J. BoURGEoIs. 

